Snowplow



Feb 10, 1931. R F. SYMONDS sNowPLow .Filed July 26, 1928 Patented Feb. 10, 1931 UNITED STATES PATENT oFFICE RALPH F. SYMONDS, OF MARBLEHEAD, MASSACHUSETTS, ASSIGNOB T0 NEW ENG- LAND STRUCTURAL PRODUCTS CO., OF EVERETT, MASSACHUSETTS, A CORPORA- mm or MASSACHUSETTS SNOWIPLOW Application filed July 26, 1928. Serial No. 295,483.

This invention relates to snow plows and particularly to those for use with tractors.

In one aspect, the invention consists in an improved snow plow for cleaning sidewalks, gutters or streets where an uneven surface must be followed, where obstructions such as curbs'tones must be reckoned with and where the plow must be directed through narrow places and past trees and posts. To this end, the plow of my invention, although strongly supported to withstand great pressure of snow, has a capacity for self-adjustment or accommodation to the terrain over which it may be driven not found in plows as heretofore constructed. For example, the plow as a whole is mounted for rocking movement about a longitudinally disposed axis so that it may follow variations in the transverse slope of the surface beneath it. In the second place, the plow as a whole is mounted so that it may be lifted bodily in order that it' may be carried at the requisite distance above rough ground and, in the third place, the plow has provision for tilting about a transverse axis so that its vertex or prow may be tilted upwardly, as in passing over a curb. While these various features of self-accommodation or adjustment individually involve novelty, the construction by which they are made available simultaneously in a unitary device is of great practical importance and constitutes an important feature of the invention.

Another feature of importance consists in a wing extension for varying the effective width of the plow as a whole. As herein shown, the converging plow members are supported by a frame which, in turn, is adapted to bemounted upon the chassis of the tractor.

The wing extension of my invention is preferably mounted upon the same frame -to swing about a substantiall wherein the plow is effective in its minimum width, or may be maintained in any inter- 7 vertical axis andis connected with controllmg means extendmediate position with a corresponding variation in the effective width of the plow.

In another aspect, the present invention consists in a snow plow particularly rigid, strong and reliable in its construction and embodying to a large measure in its design structural steel plates and angles which are available in commercial sizes. From this standpoint, other features of the invention, accordingly, consist in a supporting frame comprising spaced angle bars extending between the converging plow members and connected to the mold board through the medium of a curved angle plate. As herein shown, angle plates are also'secured to the spaced angle bars and these are utilized toconnect the supporting frame with a rocking bolster having vertical slots in opposed flanges and forming a part of the connection from which the desired vertical and tilting movements of the plow are derived. As herein shown and as a further feature of the invention, longitudinally disposed trunnion which is carried by spaced plates secured to the chassis. The plow construction, which includes a heavy flanged plate or bolster mounted for rocking movement about one axis and con-' nected to and carrying the plow in itsentirety, has not been used heretofore and constitutes in itself an important feature of the invention.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof, selected for purposes of illustration and shown in the accompanying drawings, in which Fig. 1 is a view in perspective ofthe plow mounted upon a tractor;

Fig. 2 is a sectional view, on an enlarged scale, on the line II of Fig. 1; and v Fig. 3 is a view in perspective illustrating the bolster and its mounting upon the chassis frame.

In the accompanying drawings, the snow plow is shown as mounted upon a tractor of commercial type but it will'be understood that its use is not limited to this or to any particular make of tractor.

the rocking bolster is supported upona As herein shown, the side frame members 12 of the tractor are of angle bar construction and slope downwardly toward the front of the tractor. To these bars is secured a plate 14 flanged at its upper end to fit the side frames 12 and riveted securely thereto. Projecting downwardly from the center of the chassis is a post 16, a portion of which is shown in Fig. 3, and to the lower end of this is rigidly secured a shoe or spade 18 extending upwardly at its forward end and carrying an angle plate 20, which extends upwardly in spaced relation to thedownwardly extending plate 14. The plate 14 and the angle plate 20 form a support for a trunnion 22. Mounted for rocking movement upon the trunnion is the bolster 24 which consists in a heavy flanged plate of substantially the same width as the plate 14 and has at its edges forwardly extending opposed flanges, each of which is provided with a vertical slot.

The lower edge of the bolster 24 slopes downwardly on each side from the opposed flanges, so that the axis of the trunnion 22 in the bolster is located entirely below its slotted flanges. A hinge pin 26 extends through the slots of the flanges of the bolster and upon this is mounted the plow itself.

The plow members comprise a concave mold board 36 and a flat draft board 40. These converge forwardly and are connected to form the vertex or prow of the plow. The draft board carries a replaceable shoe, compr1s1ng a strip 42, and the mold board is equipped with a renewable runner 38 which is held in place by a line of rivets but may be replaced when it becomes worn. To the rear or convex side of the mold board is secured, by rivets 35, a curved angle plate 34 which is disposed substantially vertically with its flange normal to the curve of the mold board. Between the two plow members 36 and 40 is a frame comprising a pair of spaced angle bars 30. These are connected dlrectly to the draft board 40 and by means of an interposed angle plate 32 to the mold board 36. The angle bars 30 are connected by an intermediate plate 50 and at either end by angle plates 28 which extend rearwardly in parallel relation and are perforated to receive the hinge pin 26. It will be apparent,

that the plow in its entiret may be lifted within the range permitted y movement of the hinge pin 26 in the slots of the bolster flanges or that it may be rocked about the axis of the hinge pin.

, The mold board is supported from the ground near its outer end by a shoe 46, secured at its rear end to the lower edge of the plate 50' and in its forward or outer end to the lower edge of the mold board through the medium of an angle plate 44 and bolts 48.

Each of the angle bars 30 carries at its left end, as seen in Fig. 1, an outwardly extending hinge plate 71, between which extends a hinge pin 74 which constitutes the axis of the wing extension 70. The wing extension has spaced inwardly extending flanges which are perforated to receive the hinge pin 74, the axis being so located that when the wing extension is swunginto its outward or operative position, it constitutes, in effect, a continuation of the mold board. The position of the wing extension is controlled by the operator through a lever 86, arranged adjacent to his seat and connected through a link 84 to a cross head 78, slidably mounted on the right-hand side frame of the chassis. The cross head carries a guide rod 80 which slides in a perforated angle piece 82 secured to the side frame 12 and forming a guide member for the rod. An eye 81 extends outwardly from the cross head 7 8 and is pivotally connected to the rear end of a connecting rod or link 76 which, in turn, is pivotally connected at its forward end to the flange plate 72 of the wing extension 70. In Fig. 1, the wing extension is shown in retracted or inoperative position. When, however, the operator swings the lever 86 rearwardly, the cross head 78 is advanced and the connecting rod 76 acts to swing the wing extension outwardly and hold it positively in whatever position it may be set.

Vertical and tilting movement of the plow as a .whole is controlled by a lever 68 located within convenient reach of the operator and connected through a chain 66 to the rear end of a lever 58. The lever 58 is fast to the right-hand end of a transverse shaft 56 journaled in bearings'secured to the side frame members 12. The lever 58 is extended forwardly beyond the shaft 56 and connected by a link 60 to an an le iron 62, secured to the inner face of the raft board 40. A forwardly extending arm 54 is secured to the left-hand end of the shaft 56 and this is connected through a link to an angle iron secured to the plate 71 which, in effect, is a part of the frame of the plow.

It will be understood that when the lever 68 is swung toward the rear, the arm 54 and the forward end of the lever 58 are lifted. The points of connection are such that the plow is lifted bodily until the hinge pin 26 reaches the upper end of the slots in the flanges of the bolster 24 and thereafter the plow is rocked upwardly about the hinge pin 26 as an axis. It will be apparent that in this movement of the plow the wing extension 70 is also bodily moved, being carried by the frame thereof, and on account of the play in the connections to the wing extension supplied by the connecting link 76, it may be swung in or out in all positions of the plow.

The design and shape of the draft board 40 and mold board 36 is such as to substantially balance the lateral or transverse pressure upon the plow as it is driven into the snow.

said trunnion and havin The mold board 36 has a concave curvature and, accordingly, acts to roll up the snow it encounters instead of displacing it by a wedging action. The draft board 40, on the other hand, has a plane surface and. diverges slightly from the line of direction so that it pushes the snow out of its path and thus develops a substantial lateral pressure. The forward end of the draft board, which extendsv beyond the vertex of the low, acts in a measure as a rudder to steer t e plow into the snow in a straight line.

The shoe or spade 18 which, it is understood, is located substantially between the front wheels of the tractor is effective as a runner to assist the wheels in lifting the tractor over a curb or other obstruction.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A snow'plow comprising a frame adapted to be secured to a tractor chassis, a longitudinally disposed trunnion carried by the frame, abolster mounted to rock upon said trunnion, and plow members mounted upon said bolster to rock about a transverse axis.

2. A snow plow comprising a frame, atrunnion carried by-the frame, a rocking on bolster mounted upon the trunnion and having spaced vertically disposed slots therein, plow members, and a single transverse shaft passing through the slots of the bolster and connecting the plow members thereto.

3. A snow low comprising a frame adapted to be rigi y secured to a tractor chassis and carrying a lon 'tudinally extending trunnion located relatively near the ground, a bolster mounted to rock transversely upon opposite y disposed flanges at either e ge located above the trunnion, and converging low members pivotally mounted upon the anges of said bolster.

4. A snow plow comprising a supporting frame, a rocking bolster connected thereto, a second frame having a pin and slotconnection with said bolster; permitting vertical movement thereof, diver ing plow members carried by the movable me, and a single .manually operated device for first lifting said movable frame and then swinging it to elevate the vertex of the plow members.

5. A snow plow for use with a tractor, comprising a plate and a shoe secured to the tractor chassis and spaced from each other, a trunnion supported thereby, a rocking bolster carried by the trunnion and plow members carried by the bolster.

6. A snow plow for use with atractor, comprising a frame adapted to be supported upon the. tractor chassls for vertical and also tilting movements, a wing extension pivotally mounted upon said frame for movement about av substantially vertical axis, and manually operated means including a for swinging said wing extension said link being pivotally connected to said means to permit tilting of the frame without interfering with the action of said means.

7. A snow plow for use with a tractor, comprising a frame adapted to be supported upon the tractor chassis, converging plow members carried thereby, a wing extension for one of said members supported for movement about a substantially vertical axis, a cross head guided for horizontal movement upon .the chassis, connections between said cross head and said wing extension, and means for operating said cross head.

8. A snow plow for use with a tractor, comprising a plate adapted to be secured to the forward end of the tractor chassis, a bolster mounted upon said plate and having slotted opposed flanges, plow members carried .by

v the flanges of said bolster, and levers .mounted upon the chassis and connected to the plow members for liftingthe plow in its entirety within the range permitted by the slots.

9. A snow plow for use with a tractor, comprising a frame, a mold board and a draft board mounted thereon for tilting movement about a transverse axis, a Wing extension pivotally mounted adjacent to the outer end of the mold board, and separate operating means adjacent to the operators seat for controlling the tilting of the plow and the position of the wing extension.

10. A snow plow for use with a tractor, comprising a rocking and tilting frame, plow members carried thereby, a wlng extension piv'otall'y mounted upon said frame, a wing controlling lever pivotallymounted upon the tractor chassis, and connections between said lever and wing extension for swinging the latter in all positions of said frame.

' RALPH F. SYMONDS. 

